Manulea silenoides is an erect to spreading annual reaching heights from 1 cm to 20 cm, usually smaller than 10 cm. There are glands or balloon-tipped hairs on the stems.
The leaves are elliptic to oblanceolate, mostly forming a basal rosette. The stem-leaves occur only lowdown, are smaller, narrower than those forming the rosette. The leaves have entire margins, the blades sparsely hairy.
These Namaqualand plants are endemic to the Northern Cape, growing widespread in sandy soils on flats to the escarpment. The species is not considered to be threatened in its habitat early in the twenty first century (Manning, 2009; Le Roux, et al, 2005; Leistner, (Ed.), 2000; iNaturalist; http://redlist.sanbi.org).